Introduced less than a month ago, Honda Malaysia's special edition Civic RX has been enthusiastically received by dealers and Civic fans. Indeed all 60 units are reported to have been taken up by Honda Malaysia's dealers, with dealers as well as customers demanding for more ! This is not that surprising since the Civic RX was designed to specifically appeal to the enthusiast while dealers really welcomed the refreshing difference a sporty and good looking Civic brings into the local line-up.
The Honda Civic RX is designed to be the base for further modifications according to personal tastes. With the looks and interior already taken care of by Honda, the obvious area for the enthusiast to work on next would be the car's performance. So in this follow-up article, I look at a most interesting question : given Honda Malaysia's Civic RX as the base, what would be some options for some nice performance gains, for that little extra 'oomph' so to speak, from the car ?
In terms of the peformance of a car, TOVA has always look at it in terms of a whole package. To me, the performance of a car can be roughly divided into three main areas. First would be the issue of outright engine power - the area most commonly looked at by the enthusiast. But other areas are of equal if not greater importance. The handling of the car is also an important element of a car's performance - we certainly do not drive in straight lines only ! The third area is perhaps the most important area, despite it being often overlooked by enthusiasts and that is the car's stopping power. After all, if we want to go fast, it is even more important to be able to stop faster !
To cover all three areas, we take a look at two different ES-Civics in this article. First we start with the base, Honda's Civic RX. Honda Malaysia was eager to pass me the car for a TOVA-style review. The fact that the RX do not have any power upgrades may on the surface suggest an uninteresting review. But the RX that Honda Malaysia passed to me is fitted with the optional Honda Access Sports Suspension so it is upgaded in the important area of handling. For power and braking upgrades, I have an ES-Civic VTi as the case study which has a very simple power and brake mod package.
In strict terms, even for the owner of a basic Civic RX, there would already be a discernible handling upgrade over the regular Civic VTi. This is due to the larger 16" rims and 205/45VR16 tyres. Having lower profile tyres means a thinner side-wall and therefore less sidewall flex. This has the equivalent effect of a harder suspension. Ride quality is harder but handling during hard cornering is correspondly better too.
The Honda Access Sports Suspension that is fitted to the review Civic RX is specially designed by Honda Access to give the standard ES-Civic an upgraded handling more in line with that from a performance oriented car but still with acceptable ride comfort. It consists of shorter, stiffer springs with matching absorbers. Visually, the springs are yellow in colour while the absorbers (or shocks as enthusiasts likes to call it) are red in colour as shown in the photo on the right.
With upgraded performance suspensions, the first important question for the enthusiast would be how much drop in ride height the suspension gives. The standard 'enthusiast measurement' for ride height is the rather unusual but popular 'number of fingers' between the top of the tyre and the fender. This is not terribly accurate or consistent of course since besides being unable to be consistent in the angle at which the fingers are placed, different persons will have fingers of different thickness ! A much better measurement method would be to measure the distance from the point at which the tyres touches the road to the fender, as illustrated by the photo on the left. All four sides of the car should be measured and for simple enthusiasts type comparison, the average can be used. When conducting the measurements, it is good to ensure the car is parked on as level ground as possible. The tyre pressure should be at the recommended level too.
To establish a baseline reference, we of course use the figures for the standard Civic VTi. This came out to around 650 mm for the front driver's side and 665 mm for front passenger's side. For the rear, it came out to 660 mm for the driver's side and 675 mm for the passenger's side. The measurements are quite consistent and works out to an average of around 662 mm for the car. To readers from outside of Asia, I want to highlight that Malaysian cars (and for that fact, most Asian cars) are right-hand-drive.
Measuring the same points on the Civic RX, the measurements are now 623mm for front driver's side, 630mm for front passenger's side, 639mm for rear drivers side, and finally 644 mm for rear passenger's side. This works out to an average of around 634 mm for the car. Comparing to the standard measurements, therefore in absolute terms, the sports suspension gives a drop of approximately 28 mm or ~ 1.1 inch in ride height. The standard Civic VTi is spec'ed for a ground clearance (distance between the lowest point in the car and the road surface) of 155 mm or approx 6.1 inch so the ground clearance with the sports suspension would be around 5.0 inch (~127 mm).
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Getting on to the other important areas. Visually, even a regular Civic RX (i.e. with the 16 inch wheels but stock suspension) has a quite large gaps between tyre and fender. The car sits rather high on the wheels, somewhat giving the impression of an unloaded pick-up truck especially the rear. This can be clearly seen from the photo on the left. With the sports suspension, the gap at the top is closed up rather nicely and the gap between tyre to fender is now small and even all round. The second photo shows a Civic RX with the sports suspension.
A drop of only around 1 inch for a ground clearance of 5.0 inch should not seriously detract from the practicality of the Civic RX in day-to-day driving. Cars with lowered suspensions faces two main problems. First there are the badly designed speed-breakers which are too narrow and too tall, causing the undercarriage to scrap along the top of the hump. Then there are the access ramps in multi-storey car-parks. These are often too short making them very steep which causes clearance problems for car's front lips. Then where the ramp joins the upper floor, it often 'overshoots' above the floor level. Builders then take the easy (and cheap) way out and simply fill up the resultant gap with concrete effectively creating a little 'ridge' right at the point where the ramp meets the upper floor. An example is shown by the photo on the right. I think many are well familiar with the pain from hearing that brand new JASMA-approved mandrel-bent stainless steel exhaust system go screeching along the top of such a ramp !
During my review, I drove the Civic RX into my IBM office building's basement carpark, shopping complex car-parks and also to many places with a lot of speed breakers. I could negotiate practically all the speed-breakers and car-park ramps that I encountered. Most of them I could even go through with a little bit of speed. The stiffness of the spring/shock combination even seems tuned for the job as I could go through them even at speeds of up to 5-10kph.
My office building's basement carpark has 3 very bad ramps. While not actually the worse I have encountered it still ranks up amongst the top ! The worse of the lot is the last one which leads to the exit/payment booth. As an illustration of how bad it is, a completely stock EJ-Civic (Malaysian spec EK-generation Civic sedan) loaded with 4 adults is unable to clear the ramp without the entire undercarriage scraping along the apex of the ramp. The HM Civic RX fared surprisingly well. Firstly, I could negotiate the other two ramps easily. For the last ramp, with only me in the car I could still clear it by slowly easing the car through. But with one passenger, or even when alone and going a little bit faster than a crawl, the car still lightly scrapped the apex.
In terms of ride quality, I drove the Civic RX over many different road surfaces, and also intentionally run over very small potholes (taking care not to endangear the rims of course) and found the ride quality to be generally OK from the driver's seat. By generally OK I mean that although I could feel the stiffness of the springs but at low speeds (up to 50-60kph) the sports suspension could surprisingly still soak up small road irregularities, small potholes, little bumps, etc pretty well - i.e. I couldn't feel them, only know vaguely that the road is not perfectly flat and the RX pretty much goes through holes with a very soft and dull 'boob'. At higher speeds however, the car began to follow the contours of the road a bit too 'literally' causing mild pitching. Unfortunately this gets pretty bad on our national highways and expressways when travelling at speed limits (100kph to 120kph) - the unevenness of the road surface became very obvious as the car pitches around quite a bit.
HandlingBut the enthusiast really buys the sports-suspension for its improved handling and not for its ride quality so this should be what we should focus more on. Over the extended weekend - though I never really pushed the RX to its absolute handling limits (it's not my car after all) I nevertheless engaged in quite a bit of pretty aggressive, spirited driving in order to check out the car's handling.
When I drove the HM RX aggressively I found I could do it with a good degree of confidence. The RX was actually quite easy to get up to a fast speed (up to 90-110kph) and when driving so, it was easy to keep the car in line, even around bends. When there's a need to change the driving line rapidly, the car exhibited good stability. For example, in one case after changing into the middle lane to overtake a row of stubborn cars hogging the fast lane, a slow moving Kancil (a very popular Malaysian made K-car) cut in front of me from the left lane. As a result I had to quickly swerve into the left lane, overtake the Kancil and then swerve back into the middle lane, complete the overtaking of that row of stubborn cars and finally back to the fast lane, completing the 'extended' overtaking manuerve. Throughout this maneuvre, body-roll did not interfere with the manuevre nor affect the car's stability. Actually eventhough there were body-roll it was hardly noticeable in all the excitement.
When taking a wide corner at high speeds (80-100kph), I was able to make small changes to the cornering line (by small adjustments to the steering wheel) and this time the car did not exhibit any obvious body-roll, perhaps because the suspension was already pretty much compressed by the cornering. And when 'throwing' the car into very tight corners, as long as I exercised common-sense and restraint and took the proper line, the RX complete the manuevre without any drama. The car felt very stable and confident through the corner but body-roll was noticeable on entry and in the corner. Going at low-ish speeds in a straight line, if I rapidly twitch the steering wheel (rolling it left and right), the car responds linearly to the steering input again with perceptible but light body-roll.
In the end, we need to bear in mind the Civic RX's base is still a family sedan. Yes, as its name suggests, the sports suspension is designed to give the RX a 'sporty' handling. But I think it will be unreasonable to expect the sports-suspension to elevate the RX's handling to that of a purpose built performance car. I think a very good standard by which to judge the Civic RX with Sports-Suspension would be either an EG9 or EK4 Civic Ferio SiR. This would be a personal evaluation now but based on experience, I do think in terms of handling, Honda Malaysia's RX actually exceeded the capability of a stock EG9 SiR but with a harder ride quality. Readers should bear in mind this is acheived via a combination of larger 16" wheels, lowered ride height and the custom designed Sports-Suspension.
Readers would be correct if they conclude that I am sufficiently impressed by Honda Malaysia review Civic RX, especially the Honda Access Sports-Suspension. This view is actually shared by members of my Honda club who have driven the car briefly, including an ex-member who has since changed his car to an E36 BMW 325i. I think the optional Sports-Suspension for the Civic RX is a very worthwhile upgrade and indeed for those who are in the midst of purchasing the RX, I would go so far as to recommend they spend the extra for this option. It really do upgrade the handling of the Civic RX significantly.
With the question of handling upgrade pretty well covered, I now take a look at the other two areas; power and braking.
The ES-Civic uses a D17A engine. It is SOHC-VTEC in configuration but the VTEC implementation is an evolution of that on the older VTEC-E from the EG Civics. The engine runs in 12V mode until reportedly around 3000rpm where it changes to 16V mode. Spec'ed to deliver 130ps, Honda designed it to deliver very good low and mid-range power. After driving the RX for a while, I feel Honda designed the ES-Civic to drive like the equivalent 'continental car' : very good response on take-off (squeeze the throttle and the car 'jumps' forward nicely) and very good mid-range. But similarly, the engine runs out of breath at high-rpms. For normal driving, this actually gives the impression of a powerful engine because the car surges nicely forward at normal speeds and since most people don't push the engine to its red-line, the short-coming at high rpms may not even be noticed ! Therefore for normal overtaking manuevres, when we just want to get ahead of the car in front, the RX actually drives very well. Switch lanes, gently squeeze the throttle and the car surges forward. The Grades Logic Control gearbox helps a lot here. When cruising, the gearbox stays in 4th gear. Run at 90kph and engine rpm hovers around 2200 to 2300rpm. Squeeze the throttle and the gearbox immediately switches to 3rd gear (the gear shift is hardly felt) and the rpm jumps to just below 3000rpm. With the engine's good midrange, the car completes the over-taking with ease. The problem comes when we are over-ambitious; Honda enthusiasts who are used to the very wide power band of previous VTEC engines, often likes to overtake several slower moving cars in one go, expecting the engine to continue pulling right to the red line. It does but the car rapidly loses steam as it nears the red-line. I actually had to abort a few such overtaking attempts after running out of space !
The stock brakes of the RX are quite effective but the brake feel is unfortunately a bit spongy. After feeling the brake pads bite initially, press some more and the pedal gives way relatively easily. When braking from high speeds, the brakes initial bite fails to slow the car sufficiently. So we press the pedal harder. The pedal gives way under the hard pressure and then only the brakes bites hard and rather suddenly too. This sort of unlinear brake feel leads to unconfident braking, especially at high speeds.
'HKS' Civic VTi
Lim is a member of my Honda club. Previously driving a local-spec EK-Civic (coded locally as EJ), Lim upgraded to the Malaysian-spec ES2 Civic VTi when it was launched here in Malaysia. So in many ways, Lim represents the typical Civic fan. After 2 years of using his car, with the warantty period expired, Lim decided to 'invest' in some mild mods to his beloved car. For the power side, Lim took the trusted route of air-filter and air-fuel controller. Being the wise enthusiast, Lim also paid attention to his braking system. All other areas of his car are stock.
In the power area, Lim's VTi has a HKS Super Power Flow open element 'mushroom' air-filter. The entire air-intake box assembly is removed for its installation. The stock air-intake box is actually quite a large construct on the D17A which has the throttle body unusually facing up-wards, the intake runners fanning out from the throttle body to the four cylinders. The stock 'panel' air filter box sits on top of the throttle body, with the filter box connected to a rather huge resonator box and then a pipe taking air from the right (driver's) side of the engine bay. Indeed visually the filter box dominates the engine bay ! This complex structure is shown clearly on the photo above. Installing the Super-Power-Flow entails removing this whole structure and replacing it with a custom aluminium pipe. The pipe physically places the air-filter in the space vacated by the large resonator box. There are some rubber hose connections to that were retained by welding connectors to the aluminium pipe. Lim's Civic engine bay is shown on the left.
The HKS AFR air-fuel ratio controller is already well known. A relatively simple device, it works by intercepting the MAP sensor signal before it enters the ECU. A dial allows the MAP sensor signal to be increased or reduced and this give the equivalent effect of 'tricking' the ECU that more or less air is flowing into the engine, thus indirectly influencing the air-fuel ratio in the engine. Air-fuel ratio controllers should be set using a dyno facility that has a wide-band O2 sensor to measure the engine's air-fuel ratio. Lim actually bought the Super-Power-Flow and AFR as a package, complete with installation and dyno-tuning on a Dynojet.
For the braking system, Lim replaced the stock rubber brake hoses which feeds into the brake calipers with steel braided teflon hoses. Shell DOT-4 brake fluid was also used. The standard rubber hoses are prone to bulging under very hard braking, especially after extended usage when the brake fluid and the brake pads themselves have heated up significantly. When the rubber hoses bulges, it gives that spongy feeling to the brake pedal and more importantly prevents the brake pressure from building up linearly. Thus as would be expected from theory, with the brake hoses upgrade, Lim's VTi gives a firmer brake pedal feel. More importantly brake feel was significantly improved, with retardation quite linear and proportional to brake pedal pressure. I asked Lim for his evaluation and he says he's sure the braking 'power' of his car has improved.
The 'before and after' dyno chart for Lim's Civic VTi with the HKS filter & AF controller is on the left. As explained previously, after fitting the Super Power Flow, the AFR is tuned on the dyno for optimum power output. The D17A engine is of the new generation design, without a distributor and with individual ignition coils on top of each spark plug. There is now no base distributor timing to speak off, ignition timing is totally controlled by the ECU. So unlike for previous generations of Honda's engine (the legendary B-series for e.g.) ignition timing adjustments via tuning the distributor are not applicable for the D17A.
Analysing the dyno result, stock, Lim's car is already delivering a surprising amount of power at the wheels, actually quite a bit more than what would be expected from our previous experience with the standard Honda automatic (non Grades Logic Control) gearbox. From 130ps at the engine, our past experience suggests a 30% power loss for a normal discrete ratio automatic (i.e. non-Multimatic) gearboxes which works out to 91ps at the wheels. But Lim's VTi dyno's at 97.6ps atw and this translates to around 140ps at the engine using the standard 30% power loss ! This means either the specs for the D17A engine is seriously 'under-declared' or the modern Grades Logic Control 4AT actually have superior (i.e. less) power loss characteristic. If we assume the latter case, 97.6ps over 130ps works out to ~25% power loss for the GLC 4AT gearbox. For this article, we will work with this new figure.
With the HKS bolt-on package, dyno-tuning allowed Lim's VTi to deliver 100.2ps at the wheels. Working with the new 25% power loss figure, this works backwards to around 134ps at the engine, a pretty good 3% power gain. Indeed, the max gain across the power band probably nears 5ps at the wheels. Unfortunately there are also some power loss in the midrange, between 3,000rpm to ~4,300rpm which is rather unexpected. I think this shows that the resonator box on the stock filter assembly is an integral part of the design and other than just noise suppression, the dyno result evidently shows that it gives benefits to air-flow efficiency in the midrange (via the resonance effect) thus benefitting power in that area as well. The loss of this effect is probably what led to the loss in midrange power.
Nevertheless, the gains in the top-end is still pretty good, and this with a very simple package of open-element filter and air-fuel controller. With additional complementary mods like free-flow muffler and matched headers, I think even more gains can be confidently expected !
On the road I only had a brief driving test of Lim's VTi. Comparing to the review Civic RX, Lim's VTi felt slightly more powerful at the top end. Lim himself told me he did not feel any real improvements from the package, eventhough the dyno tells him otherwise. But he was full of praise for the improved fuel economy, most probably due to the now optimised air-fuel ratio from the HKS AFR. Comparing to the HM RX which has a completely stock engine, I could actually feel the mid-range power is lesser on Lim's car, perhaps with the benefit of hindsight after seeing the dyno-chart. There's less 'urge' in the car especially when going WOT from modium to low speeds but conversely, the car pulls very consistently all the way up to the red-line.
Results do speak louder than opinions of course. One encounter involving Lim's VTi that I can relate was during one of my club's recent cruises. We were cruising comfortably on the expressway within speed limits but on the fast/overtaking lane when an EK4 SiR with Singapore plate came right up to his tail and gave him the 'flash-treatment'. With traffic rather sparse, Lim allowed the EK4 through and proceeded to have some fun with that car, trough tailing him and returning the flash compliment. In doing this, Lim's VTi was rather impressive - he was easily able to tail-gate the EK4 SiR until quite high speeds, 140kph and above, and only started to be left behind when speeds started approaching 160kph or more. Traffic was sparse but there were still the occasional cars blocking the fast lane so the EK4 was unable to shake Lim off no matter how hard he tried. In the end, the guy actually gave up on the game and swerved back into the middle lane ! Yes, that EK4 SiR was most probably an auto but so is Lim's VTi so for an executive SOHC-VTEC to be able to keep up with a DOHC VTEC on the open highway is quite an acheivement indeed.
So the blueprint for a nice mildly modified enthusiast ES-Civic is clear. Honda Malaysia's Civic RX forms a very solid base. Highly commended is the optional Honda Access Sports Suspension. For power and braking upgrades, the enthusiast can further customize the RX by using the sort of bolt-on package similar to that on Lim's Civic VTi. It's a personal opinion of course but the sports suspension-16" wheels package do give the Civic RX significantly improved handling, quite in-line with that of a sports-sedan while the power gain from a modest yet properly matched bolt-on package is not something that can be trivialized too. Just like what Lim did, it is also important to take care of the brakes as well. If done properly like in this way, I think the conceptual Civic RX with HKS Super-Power-Flow & AFR and steel braided brake hoses as a package as an example might very well be quite near in performance to a stock auto EK4 SiR, with similar braking abilities, better handling, better midrange power but still losing out in the high-end. Yes, a suitably customized Civic RX will be quite potent indeed !
The best thing of course is that things works both ways. For current owners of Civic VTi's, the Honda Access bodykit complete with the 'RS' mesh grille can be ordered from Honda dealers and retrofitted to their cars. They can even do the leather seats and purchase the special 'RX floor mats' if desired and this will take care of the looks. And of course the power/brake-hose package takes care of the rest.
The ES-Civic is probably the least exciting Civic for a long time. Yet it has its own set of strengths as well as its own set of fans. For Malaysian fans at least, Honda Malaysia injected a much welcomed sense of life and excitement with its special edition Civic RX. This quickly opens up a lot of options for a good-looking well-equiped Civic which if additionally fitted with even just mild bolt-on mods by the owner can become quite a fast car too. Life's no longer dull with the current Civic !
As with all our current articles, readers who wishes to discuss about this article are encouraged to join our special "Modifying the Civic RX" thread in our TOVA forum.
Wong KN
April 2003
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